Electric incandescent lamp.



M2187@ ess es.

PATENTBD MAY 8,1906.

C. SCHBBL.

ELECTRIC INGANDBSGENT LAMP.

APPLICATION FILED SEPT. 25. 1905.

ject of the German Emperor, residing at Vi` UNITED STATES PATENT orrion.

CARL SCHBEL, OF 'VIENN A, AUSTRIA-HUNGARY, ASSIGNOR 'IO THE FIRM OF ELECTRISCHE GLHLAMPEN-FABRIK WATT, SCHARF &' CQ., OF VIENNA, AUSTRIA-HUNGARY.

ELECTRIC I NCANDESC-ENT LAMP.

--To all ivhom it may concern:

l Be it known that I, CARL SCHBEL', a subenna, Austria-Hun ary, have invented certain new and usefu Improvements in Electric Incandescent Lamps, of which the following is a specification.

In electrical incandescent lamps the leading-in wires which are admitting the current to the carbon filament must be made'of platinum in as far as they pass through the glass wall of the bulb. Endeavors have been made to reduce to a minimum the quantity 'of the platinum employed. For this purpose to short platinum wires have been soldered on either end wires made of other metals, and the platinum wire, vtogether with the soldering-places, have been sealed in the glass of the bulb. This method is, however, connected with inconveniences.

' possesses the same coefiicient of ex ansion as glass, whereas the soldering-places o not possess this coefficient'of expansiomit is obvious that the repeated eX ansion and contraction of these soldering-p aces will produce ine cracks in the glass which sometimes will continue and extend also along the platinum wires, with the result that the outer air will vpenetrateintothe interior of the lamp.` If the solderin -places are arranged outside the place of sea ing-that is to say, outside the glass bulb of the lampthe leading-in wires will be very much liable to become bent.

According to the present invention the said inconvenience is entirely obviated in such a manner that the lower solderinglace which connects the leading-in wires to t e latinum wire is situated freely outside the g ass bulb and is maintained in place by means of a glass bridge which is rigidly connected with the glass bulb of the lamp. In this manner the soldering-place is situated outside the lam bulb, and at the same timethe bending of 't e platinum wire at the sealing-place is absoutely impossible.

The accompanying drawings represent several forms of execution of the subject-matter of the invention.

' Specification of Letters Patent.

Application filed September 25, 1905. Serial No. 280,047.

Since only platinuml .Patented May s, 1906.

Figures 1 and `2 represent the said improvement applied to ordinary incandescent amps, whereas Fig. 3 represents the application of the invention to a so-called miniature lam In the orm of executionshownin Fig.. 1

a glass bridge a is fused with both ends to th'e'lamp-bulb outside the sealing-place in which the short pieces of platinum wire pass througl .the glass wall of the bulb and throughthe said bridges a pass the copper wires, which are soldered to the platinum wires. In this :manner a bending of the leading-in wires at the solderinglace is absolutely avoided.

The form o execution represented in Fig. 2 consists of a T-shaped bridge l1, in which ends of both the copper leading-in wires are" fused.

' In tlie miniature lamp represented in Fig. 3 the foot c,.wliich is formed during the manufacture of the bulb, is bent in a suitable manner, and is thus utilized for holding rigidly the leading-in wires. i

Iclaim- 1. The combination with an incandescent electric lamp having a bulb and leading-in wires; of a bridge at the bottom of the lamp to support the outer wires forming a free space between the end of the lamp and bridge, the

joint between the outer wires and leading-in wires being contained in said free space.

2. The combination with an incandescent electric lamp having the leading-in wires v sealed therein; of a glass bridge forming part of the lamp-body to support the cuter wires and forming a free s ace between the bridge and 'bottom of the amp, the vjoint between the outer'wires being contained in said 'free space. Y

3. The combination with an incandescent electric lamp having leading-in wires of a T- shaped bridge at the bottom of the .lamp to support the ends of the outside Wires and forming a free 's ace between said bridge and bottoni of the iamp, the joint between the leading-in wires and outside Wires being in said free space. 4. The combination with an incandescent electric lamp having 1eading-in Wires of a glass h'sheped bridge forming part of the body of the lamp leaving a, free space between said bodj7 and bridge, outside Wires sealed in the bridge and the j oint between the outside Wires and leading-iu Wires contained in the 'ee spade.

nesses. i CARL SCHUBELL' VVinesses GUSTAV PHI-LIPPITSCH,

ALVESTO S. HOGUE. 

